The dog must be trained, certified and reliable. The dog does not have to be 100% accurate
or perfect. The court has recognized the fact that “false positives” occur and dogs can be as low as 62% accurate.

The
dog must alert to establish probable cause. “Interest” or “casting” does not qualify as an alert.

1)
United States v Venema (563 F. 2d 1003 (1977) Tenth Circuit

Statement in affidavit for search warrant that dog which
had allegedly detected the presence of narcotics in a locker, was a “trained, certified narcotic detector dog,”
was sufficient to the judge.

2) United States v Klein (626 F. 2d 22 (1980) Seventh Circuit

Affidavit for search
warrant was not deficient by failing to show the reliability of the dog where the affiant told the judge that the dog “graduated
from a training class in drug detection in _________” and “has proven reliable in detecting drugs and narcotics
on prior occasions.”

3) United States v Viera (644 F. 2d 509 (1981) Fifth Circuit

Warrant to search suitcases
was supported by probable cause, based upon statement in affidavit that one dog who positively alerted to the suitcase had
successfully discovered drugs on 409 occasions, and another dog in over 100 instances.

4) United States v Sentovich
(677 F. 2d 834 (1982) Eleventh Circuit

Evidence that dog had been trained in drug detection was enough to establish
reliability of the dog for purposes of search warrant application.

5) United States v Lewis (708 F. 2d 1078 (1983) Sixth
Circuit

A specially trained police dog sniffed an array of checked airline baggage. The dog displayed “not a strong
positive reaction” to a suitcase.

The suitcase flew to its destination where another drug dog sniffed an array
of suitcases, including the original bag. This dog exhibited a “positive reaction for controlled substances.”
A search warrant was obtained based upon this alert.

6) United States v Spetz (721 F. 2d 1457 (1983) Ninth Circuit

A
dog sniff can support probable cause for a search warrant, only if sufficient reliability is established.

Where a search
warrant affidavit stated that two detector dogs had independently alerted to a vehicle, and one dog had previously alerted
correctly on 60 of 66 occasions, and that the other dog had previously alerted correctly on 2 of 2 occasions, established
probable cause.

7) United States v Dicesare (765 F. 2d 890 (1985) Ninth Circuit

Conviction of defendants was proper
where defendants were provided with the actual training records of the dogs used in the searches and two chapters of the manual
on dog training.

Defendant was not entitled to pre-trial production
of dog’s training file including veterinary records and false-positive / false-negative alert records.

The dog
was certified on the day in question and had properly alerted to the presence of contraband, and the defendant was allowed
extensive cross-examination of the dog’s handler at the suppression hearing to explore the issue of dog reliability.

11)
United States v Allen (990 F. 2d 667 (1993) First Circuit

Dog sniff test of Express Mail package containing LSD generated
probable cause for issuance of warrant to search package for contraband, despite the fact that dog was not trained to find
LSD and the trained dog alerted to the package.

12) United States v Lingenfelter (997 F. 2d 632 (1993) Ninth Circuit

A
canine sniff alone can supply probable cause necessary for issuing a search warrant if the application for the warrant establishes
the dog’s reliability.

13) United States v Frost (999 F. 2d 737 (1993) Third Circuit

In an airport search,
probable cause existed for a search warrant, despite omission in affidavit that drug dog did not alert to suitcase. Affiant
would have explained that drug carriers mask the scent of drugs (as happened in this case) if he had included the dogs failure
to alert, and substantial other evidence supported probable cause.

14) United States v Diaz (25 F. 3d 392 (1994) Sixth
Circuit

Evidence showed drug dog was properly trained and reliable, the dog was trained, certified and re-certified.
The defendant’s expert, a former officer and now dog trainer, did not detract from dog’s trainer qualifications.

A
very low percentage of false positives is not fatal to finding that drug dog was properly trained and certified.

15)
United States v Delaney (52 F. 3d 182 (1995) Eighth Circuit

Affidavit stating that drug detector dog was certified in
detecting drugs and in the past three years had alerted more than 50 times in situations where narcotics were located and
that dog’s handler was certified drug canine handler and had received 76 hours of training in drug dog handling was
sufficient to establish dog’s reliability.

Because showing of reliability of dog that has
alerted for drugs is unnecessary with regard to obtaining search warrant, showing of dog’s reliability is not required
if probable cause is developed on sight as result of a dog sniff of a vehicle.

17) United States v Guzman (75 F. 3d
1090 (1996) Sixth Circuit

Although trained dog’s interest (not a positive alert) in defendant’s bag would
not alone constitute probable cause, officer’s awareness of dog’s interest may be considered by the court when
determining whether totality of circumstances established probable cause.

18) United States v Berry (90 F. 3d 148 (1996)
Sixth Circuit

Positive reaction by properly trained narcotics dog can provide probable cause; however, training and
reliability of the dog must be established.

Statements in affidavit which referred to police dog which detected the
odor of narcotics coming from an automobile which reasonably implied that the dog was trained and qualified to conduct narcotics
investigations were sufficient to training and reliability of the dog for the search warrant.

Affidavit need not describe
particulars of dog’s training and accounting of dog sniff indicating presence of narcotics. Reference to dog’s
training in narcotics investigations are sufficient to establish dog’s training and reliability.

19) United States
v Scarborough (128 F. 3d 1373 (1997) Tenth Circuit

Search warrant affidavit indicating that drug detection dog was certified,
was trained to alert to drug odors and had overall reliability rate of 92% in alerting to controlled substances and contraband,
supported finding the dog was credible.

The dog’s alert to the package (U.S. Mail) detained by postal authorities
established probable cause, even with the dog’s lower success rate of 79% reliability during its previous assignments.

20)
United States v Kennedy (131 F. 3d 1371 (1997) Tenth Circuit

Omission of information about drug dog trainer’s
failure to keep accurate records or train dog on regular basis from application for search warrant did not render invalid
warrant. The affidavit stated the dog was trained and certified and did not contain any false statements.

The omitted
information in the affidavit would still have shown dog to have 70 – 80% success rate and would have established probable
cause.

A search warrant based upon a narcotics canine alert will generally be sufficient on its face if affidavit states
that the dog is trained and certified to detect narcotics.

21) United States v Rivas (157 F. 3d 364 (1998) Fifth Circuit

“Casting”
by drug detection dog did not provide reasonable suspicion of criminal activity.

As the dog handler testified, an “alert”
is scratching and biting at an object and a “cast” is temporarily stopping, giving part of object minute attention
and then continuing with inspection.

22) United States v Owens (167 F. 3d 739 (1999) First Circuit

The existence
of probable cause to search an automobile based upon an alert by a drug dog depends upon the dog’s reliability.

Drug
dog was sufficiently reliable to support search of automobile upon arrest of driver, despite dog’s failure to pass two
certification tests, where dog was certified at time of search at issue, and both training supervisor and dog’s handler
testified as to dog’s reliability.

23) United States v Patten (183 F. 3d 1190 (1999) Tenth Circuit

An alert
from a canine with a sufficient accuracy record in detecting drugs is generally sufficient to establish probable cause for
arrest.

The canine alerted to a suitcase. Inside was ephedrine, a federally controlled chemical substance used in the
production of methamphetamine.

Even though
the officer testified that his narcotic detector dog occasionally alerted falsely and his rate of reliability was between
90 and 97 percent, the court ruled that the dog was reliable.

(This is the only case that refers to “pseudo-cocaine”
(drugs). Suspect Navarro-Camacho claimed officers smeared “pseudo-cocaine” on his vehicle so the narcotics dog
would falsely alert and give officers probable cause to search. The court concluded the officers did not plant “pseudo-cocaine”
on the vehicle.)

25) United States v Sundby (186 F. 3d 873 (1999) Eighth Circuit

Warrant affidavit sufficiently
showed narcotic detector dog’s reliability where the dog and handler were certified by the United States Police Canine
Association, the dog was trained in detection of certain illegal drugs and the dog was exposed to several (U.S. Mail) packages
at the same time.

To establish dog’s reliability, the affidavit need only state the dog has been trained and certified
to detect drugs, the affidavit need not give detailed account of dog’s track record or education.

26) United States
v Hill (195 F. 3d 258 (1999) Sixth Circuit

Narcotics detection dog was properly trained and reliable, even though the
dog’s handler testified that he did not know exactly what training he was actually required to perform with his dog,
and even though handler failed to keep records of the number of times the dog indicated “false alert.” The supervisor
of the canine unit testified that he trained both handler and dog, supervisor described those procedures and supervisor stated
the dog passed training, was certified and passed post-certification training.

27) Resendiz v Miller (203 F. 3d 902
(2000) Fifth Circuit

Drug-sniffing canine alert is sufficient, standing alone, to support probable cause for a search.

The
fifth circuit has not yet decided whether a drug dog alert alone is sufficient to constitute probable cause to arrest the
person associated with the item (currency) that prompted the alert.

Because other factors supported the probable cause
in this case, the court does not reach this question.

28) United States v Limares (269 F. 3d 794 (2001) Seventh Circuit

Affidavit
of officer which stated that trained drug detection dog, which had proven reliable in past, had alerted to presence of drugs
in a parcel, established probable cause for issuance of search warrant.

The record of this dog indicated that 62% of
dog’s alerts were followed by the discovery of drugs, and that another 31% signaled the presence of currency, many of
which likely resulted from currency with unusually high concentrations of drug revenue.

An affidavit for a search warrant
based upon a positive canine alert, need not describe training methods or give dog’s scores on final exams. It is enough
if a dog is reliable in the field.

29) United States v Gregory (302 F. 3d 805 (2002) Eighth Circuit

The drug sniffing
dog was found to be reliable based upon:

• Dog was highly trained;• Dog received satisfactory certification;• Dog performed her duties flawlessly;• Dog had never given a false positive alert.

30) United States
v Outlaw (319 F. 3d 701 (2003) Fifth Circuit

A canine’s positive alert to a suitcase found to contain phencyclidine
(PCP) was reliable, even though PCP was not one of the drugs that the dog had been trained to detect.

31) United States
v Johnson (323 F. 3d 566 (2003) Seventh Circuit

In determining whether search of defendant’s vehicle was justified
by probable cause, district court could not disregard alert by drug dog on grounds the dog’s handler did not testify
at suppression hearing, when another officer, who observed the alert from a distance, did testify. The handler was not the
only officer capable of interpreting the behavior of the dog, which was an aggressive alert, as alerting to the presence of
drugs or drug infested currency.

A drug
detection dog’s training and certification records are discoverable by the defense. These materials at issue are crucial
to defendant’s ability to assess dog’s reliability, a very important issue in his defense, and to conduct effective
cross-examination of dog’s handler.

Officers arrest of defendant was supported by probable cause were defendant
was nervous and evasive in response to routine questioning and a certified narcotics detector dog alerted to the presence
of contraband in the defendant’s vehicle.

33) United States v Ramirez (342 F. 3d 1210 (2003) Tenth Circuit

Fact
that a drug sniffing canine failed to alert on a mailed package which had been detained for investigation, did not require
that all investigation of that package cease. Therefore, the subsequent opening of the package, pursuant to a search warrant
obtained after two more canines alerted to the package, did not violate the Fourth Amendment. The factors which initially
gave rise to reasonable suspicion of the package were unchanged by the negative results of the first sniff test.

Dog
sniffs are not searches within the meaning of the Fourth Amendment.